Zimmermann Telegram

The Zimmermann Telegram is a document that was captured by British
intelligence and deciphered by cryptographers in January 1917. It played
a key role in the United States' decision to join the war, and thus
changed the course of history.

Between 1914 and 1917, Europe was divided by what would become known as
World War I. Under President Wilson, the United States
initially remained neutral. Germany was cautious to have the U.S.
involved, and pledged that they would limit submarine
warfare. However, Germany was frustrated over an effective British naval
blockade, causing enormous food shortages. It was believed that massive
submarine attacks would deprive the British from sufficient food supplies
to maintain a war. The Germans knew that unrestricted submarine warfare
would bring the U.S. into the war, but this risk was considered worth
taking, since the U.S. military was not prepared, and the war would be
over before they could build up significant forces.

In January 1917, British cryptographers deciphered a
telegram from German Foreign Minister Arthur Zimmermann to the German
Minister to Mexico, von Eckhardt, offering United States territory to
Mexico in return for joining German sides. In order to protect their
intelligence from detection, and to capitalize on growing anti-German
feelings in the U.S., the British waited until 24 February 1917 to
present the telegram to President Wilson. The telegram
was published in American newspapers on March 1, and on April 6, 1917,
the United States declared war on Germany and its allies.

Attached are the decoded and coded telegrams. The coded telegram is
signed Bernstorff because it was transmitted through the United States
and Bernstorff was the German ambassador in Washington.

TELEGRAM RECEIVED
From 2nd from London # 5747.
"We intend to begin on the first of February
unrestricted submarine warfare. We shall endeavor
in spite of this to keep the United States of
Americaneutral. In the event of this not succeed-
ing, we make Mexico a proposal or alliance on the
following basis: make war together, make peace
together, generous financial support and an under-
standing on our part that Mexico is to reconquer
the lost territory in Texas, New Mexico, and
Arizona. The settlement in detail is left to you.
You will inform the President of the above most
secretly as soon as the outbreak of war with the
United States of America is certain and add the
suggestion that he should, on his own initiative,
invite Japan to immediate adherence and at the same
time mediate between Japan and ourselves. Please
call the President's attention to the fact that
the ruthless employment of our submarines now
offers the prospect of compelling England in a
few months to make peace." Signed, ZIMMERMANN.